A “healthy” portion of America is obese now. But how will we as a country look in less than 20 years? According to a new study released by Trust for America’s Health and the Robert Wood Johnson Foundation, it’s not going to be pretty.

According to the report, appropriately titled F as in Fat: How Obesity Threatens America‘s Future 2012, more than half of the adults in 39 states could be not just overweight but obese by 2030. Colorado would remain the leanest state in the union, but about 44.8 percent of its adults would be obese in 18 years, which would be a rise of 23 percentage points from its obesity rate in 2011.

How will this effect Americans physically? A couple of highlights:

According to the report, if states’ obesity rates continue on their current trajectories, the number of new cases of type 2 diabetes, coronary heart disease and stroke, hypertension and arthritis could increase 10 fold between 2010 and 2020 — and then double again by 2030.

Obesity could contribute to more than five million cases of coronary heart disease and stroke, and more than 400,000 cases of cancer in the next two decades.

In California specifically, the percentage of obese adults could double — from 23.8 percent to 46.6 percent — between 2011 to 2030.

And this post doesn’t even include the projected increase of health care costs. Again, read the entire report; it’s startling.

It’s a disturbing projection that hopefully we won’t have to face, but everyone is going to have to do their part to take care of their own body. It’s going to take effort — a lot of effort — but when you consider the consequences, you have to know that all of the work is going to be worth it.